public class StackTraceDemo2 {
    public static void main (String[] args) {
    try {
        c();
    }catch(NullPointerException ex) {
        ex.printStackTrace();
    }
    }

    static void c() {
       try {
           b();
       }catch (NullPointerException ex) {
           ex.printStackTrace();
           throw ex;
       }
    }

    static void b() {
        a();
    }

    static String a() {
        String text = null;
        return text.toUpperCase();
    }
}

